textscreen: Add help URL functionality for windows.

This adds the ability to associate a URL with a window that gives
some extra information about it and the configuration options found
in it.

1 files changed, 80 insertions, 5 deletions

diff --git a/textscreen/txt_desktop.c b/textscreen/txt_desktop.c
index 4c9cf5c1..e56a5ee4 100644
--- a/textscreen/txt_desktop.c
+++ b/textscreen/txt_desktop.c
@@ -25,6 +25,7 @@
 #include "txt_separator.h"
 #include "txt_window.h"
 
+#define HELP_KEY KEY_F1
 #define MAXWINDOWS 128
 
 static char *desktop_title;
@@ -188,6 +189,37 @@ static void DrawDesktopBackground(const char *title)
     TXT_Puts(title);
 }
 
+static void DrawHelpIndicator(void)
+{
+    char keybuf[10];
+    int fgcolor;
+    int x, y;
+
+    TXT_GetKeyDescription(HELP_KEY, keybuf, sizeof(keybuf));
+
+    TXT_GetMousePosition(&x, &y);
+
+    if (y == 0 && x >= TXT_SCREEN_W - 9)
+    {
+        fgcolor = TXT_COLOR_GREY;
+        TXT_BGColor(TXT_COLOR_BLACK, 0);
+    }
+    else
+    {
+        fgcolor = TXT_COLOR_BLACK;
+        TXT_BGColor(TXT_COLOR_GREY, 0);
+    }
+
+    TXT_GotoXY(TXT_SCREEN_W - 9, 0);
+
+    TXT_FGColor(TXT_COLOR_BRIGHT_WHITE);
+    TXT_DrawString(" ");
+    TXT_DrawString(keybuf);
+
+    TXT_FGColor(fgcolor);
+    TXT_DrawString("=Help ");
+}
+
 void TXT_SetDesktopTitle(char *title)
 {
     free(desktop_title);
@@ -197,8 +229,9 @@ void TXT_SetDesktopTitle(char *title)
 
 void TXT_DrawDesktop(void)
 {
-    int i;
+    txt_window_t *active_window;
     const char *title;
+    int i;
 
     TXT_InitClipArea();
 
@@ -209,6 +242,12 @@ void TXT_DrawDesktop(void)
 
     DrawDesktopBackground(title);
 
+    active_window = TXT_GetActiveWindow();
+    if (active_window != NULL && active_window->help_url != NULL)
+    {
+        DrawHelpIndicator();
+    }
+
     for (i=0; i<num_windows; ++i)
     {
         TXT_DrawWindow(all_windows[i]);
@@ -217,17 +256,53 @@ void TXT_DrawDesktop(void)
     TXT_UpdateScreen();
 }
 
+// Fallback function to handle key/mouse events that are not handled by
+// the active window.
+static void DesktopInputEvent(int c)
+{
+    txt_window_t *active_window;
+    int x, y;
+
+    switch (c)
+    {
+        case TXT_MOUSE_LEFT:
+            TXT_GetMousePosition(&x, &y);
+
+            // Clicking the top-right of the screen is equivalent
+            // to pressing the help key.
+            if (y == 0 && x >= TXT_SCREEN_W - 9)
+            {
+                DesktopInputEvent(HELP_KEY);
+            }
+            break;
+
+        case HELP_KEY:
+            active_window = TXT_GetActiveWindow();
+            if (active_window != NULL)
+            {
+                TXT_OpenWindowHelpURL(active_window);
+            }
+            break;
+
+        default:
+            break;
+    }
+
+
+}
+
 void TXT_DispatchEvents(void)
 {
+    txt_window_t *active_window;
     int c;
 
     while ((c = TXT_GetChar()) > 0)
     {
-        if (num_windows > 0)
-        {
-            // Send the keypress to the top window
+        active_window = TXT_GetActiveWindow();
 
-            TXT_WindowKeyPress(all_windows[num_windows - 1], c);
+        if (active_window != NULL && !TXT_WindowKeyPress(active_window, c))
+        {
+            DesktopInputEvent(c);
         }
     }
 }